Resection of the Primary Tumor in Stage IV Colorectal Cancer: When Is It Necessary?

Colorectal cancer: Recent advances in management and treatment

Colorectal cancer (CRC) is the third most common cancer worldwide, and the second most common cause of cancer-related death. In 2020, the estimated number of deaths due to CRC was approximately 930000, accounting for 10% of all cancer deaths worldwide. Accordingly, there is a vast amount of ongoing research aiming to find new and improved treatment modalities for CRC that can potentially increase survival and decrease overall morbidity and mortality. Current management strategies for CRC include surgical procedures for resectable cases, and radiotherapy, chemotherapy, and immunotherapy, in addition to their combination, for non-resectable tumors. Despite these options, CRC remains incurable in 50% of cases. Nonetheless, significant improvements in research techniques have allowed for treatment approaches for CRC to be frequently updated, leading to the availability of new drugs and therapeutic strategies. This review summarizes the most recent therapeutic approaches for CRC, with special emphasis on new strategies that are currently being studied and have great potential to improve the prognosis and lifespan of patients with CRC.

Establishment of nomogram to predict overall survival and cancer-specific survival of local tumor resection in patients with colorectal cancer liver metastasis with unresectable metastases: a large population-based analysis

BACKGROUND AND PURPOSE

The tumour-node metastasis (TNM) classification is a common model for evaluating the prognostic value of tumour patients. However, few models have been used to predict the survival outcomes of patients with colorectal cancer liver metastasis (CRLM) with unresectable metastases who received the primary local surgery. Thus, we utilized the Surveillance, Epidemiology, and End Results (SEER) database to establish novel nomograms for predicting the overall survival (OS) and cancer-specific survival (CSS) of these patients.

METHODS

Extracted primary data on CRLM patients by local surgery from SEER database. All prognostic factors of OS and CSS were determined by Cox regression analysis. The concordance index (C-index), receiver operating characteristic (ROC) curves and calibration curves were used to further evaluate the accuracy and discrimination of these nomograms. Decision curve analysis (DCA) was executed to evaluate the nomograms for the clinical net benefit. Risk stratification analysis (RSA) was used to evaluate the reliability of them in clinical.

RESULTS

3622 eligible patients were screened and assigned to training cohort (1812) or validation cohort (1810). The age, chemotherapy, tumour grade, primary tumour site, tumour size, lymph node positive rate (LNR), marital status, and carcinoembryonic antigen (CEA) were independent prognostic factors of OS. Additionally, the age, chemotherapy, tumour grade, primary tumour site, tumour size, LNR, and CEA were independent prognostic factors of CSS. The results of C-indexes and ROC curves indicated that the established nomograms exhibited better discrimination power than TNM classification. The calibration curves demonstrated excellent agreement between the predicted and actual survival rates for 1-, 3-, and 5 year OS and CSS. Meanwhile, the validation cohort demonstrated similar results. Background the clinic context, the DCA showed that these nomograms have higher net benefits, and the RSA showed that patients were further divided into low risk, medium risk, and high risk groups according to the predicted scores from nomograms. And, the Kaplan-Meier curve and log-rank test showed that the survival differences among the three groups are statistically significant.

CONCLUSIONS

The prognostic nomograms showed very high accuracy, identifiability, and clinical practicality in predicting the OS and CSS of CRLM patients with unresectable metastases treated by local surgery at 1-, 3-, and 5 years, which might improve individualized predictions of survival risks and help clinicians formulate treatment plans.

Effect of Hospital Cancer Designation on use of Multimodal Therapy and Survival of Metastatic Colorectal Cancer: A State-Wide Analysis

BACKGROUND

Stage IV colorectal cancer (CRC) often requires multidisciplinary approach. However, multimodal treatment options (receipt of > 1 type of treatment) may not be uniformly delivered across health systems. We characterized the association between center-level cancer center designation and receipt of multimodal treatment and survival.

METHODS

The Texas Cancer Registry was used to identify patients diagnosed with stage IV CRC from 2004-2017. We identified those who received care at either: a National Cancer Institute-designated (NCI-D), an American College of Surgeons-Commission on Cancer-designated (ACS-D), or an undesignated facility. We used multivariable logistic regression and Cox regression for analysis to assess receipt of one or more treatment modality and 5-year overall survival.

RESULTS

Of 19,355 patients with stage IV CRC, 2955 (15%) received care at an NCI-D facility and 5871 (30%) received multimodal therapy. Both NCI-D (odds ratio [OR] 1.64; 95% confidence interval [CI] 1.49-1.81) and ACS-D (OR 1.37; 95% CI 1.27-1.48) were associated with increased likelihood of multimodal therapy compared with undesignated centers. NCI-D also was associated with significantly improved survival (hazard ratio [HR] 0.74; 95% CI 0.70-0.78), although ACS-D was associated with a modest improvement in survival (HR 0.95; 95% CI 0.92-0.99). Receipt of multimodal therapy was strongly associated with improved survival (HR 0.61; 95% CI 0.59-0.63).

CONCLUSIONS

In patients with stage IV CRC, treatment at ACS-D and NCI-D facilities was associated with increased use of multimodality therapy and improved survival. However, only a small proportion of patients have access to these specialized centers, highlighting a need for expanded access to multimodal therapies at other centers.

Diagnosis and Treatment of Metastatic Colon Cancer in Pregnancy First Presenting as Multiple Liver Masses: A Case Report

Colorectal cancer (CRC) is the second most common cancer in women in Japan. However, it is uncommon during pregnancy. CRC diagnosis during pregnancy is often complicated and delayed due to the overlapping of symptoms, such as abdominal pain and nausea, with those of pregnancy and the limitations placed on potential diagnostic imaging and testing because of concerns for the fetus. A 39-year-old woman was referred from a local hospital at 32 weeks gestation after persistent right abdominal pain, which prompted an ultrasound that showed multiple liver lesions suggestive of malignancy. A combination of non-contrast computed tomography, non-contrast magnetic resonance imaging, contrast-enhanced ultrasound, and colonoscopy was utilized to make a definitive diagnosis; ultimately, colonoscopy confirmed the diagnosis of colon cancer with liver metastasis. A discussion within a multidisciplinary team led to the decision to deliver at 34 weeks by cesarean section and a left hemicolectomy was performed after delivery. The neonate was admitted to the neonatal intensive care unit due to prematurity but had no other complications. Chemotherapy was promptly initiated, and treatment was continued on an outpatient basis. Diagnostic algorithms for CRC during pregnancy are not yet well-established; however, the prognosis of CRC during pregnancy is poor, and clinicians should not hesitate to perform the necessary testing and consult experts in fields such as neonatology, medical oncology, internal medicine, and gastrointestinal surgery. Early diagnosis and intervention are essential for optimizing outcomes for both the mother and the fetus.

A Review of Resection and Surgical Ablation for Primary and Secondary Liver Cancers

The surgical management of primary and secondary liver tumors is constantly evolving. Patient selection, particularly with regard to determining resectability, is vital to the success of programs directed toward invasive treatments of liver tumors. Particular attention should be paid toward determining whether patients are best served with surgical resection or ablative therapies. A multidisciplinary approach is necessary to provide optimal care to patients with liver malignancy.

Primary Tumour Treatment in Stage 4 Colorectal Cancer with Unresectable Liver and Lung Metastases and No Peritoneal Carcinomatosis-Current Trends and Attitudes in the Absence of Clear Guidelines

BACKGROUND

The treatment of the primary tumour in colorectal cancer with unresectable liver and/or lung metastases but no peritoneal carcinomatosis is still a matter of debate. In the absence of clear evidence and guidelines, our survey was aimed at obtaining a snapshot of the current attitudes and the rationales for the choice of offering resection of the primary tumour (RPT) despite the presence of untreatable metastases.

METHODS

An online survey was administered to medical professionals worldwide. The survey had three sections: (1) demographics of the respondent, (2) case scenarios and (3) general questions. For each respondent, an "elective resection score" and an "emergency resection score" were calculated as a percentage of the times he or she would offer RPT in the elective and in the emergency case scenarios. They were correlated to independent variables such as age, type of affiliation and specific workload.

RESULTS

Most respondents would offer palliative chemotherapy as the first choice in elective scenarios, while a more aggressive approach with RPT would be reserved for younger patients with good performance status and in emergency situations. Respondents younger than 50 years old and those with a specific workload of fewer than 40 cases of colorectal cancer per year tend to be more conservative.

CONCLUSIONS

In the absence of clear guidelines and evidence, there is a lack of consensus on the treatment of the primary tumour in case of colon cancer with unresectable liver and/or lung metastases and no peritoneal carcinomatosis. Palliative chemotherapy seems to be the first option, but more consistent evidence is needed to guide this choice.

Association of Surgery and Chemotherapy in Stage IV Gastroenteropancreatic Neuroendocrine Carcinoma

INTRODUCTION

The survival benefit of chemotherapy for patients with metastatic gastroenteropancreatic neuroendocrine carcinomas (GEP-NECs) is well established. However, reasons for underutilization of chemotherapy are unknown.

METHODS

The National Cancer Database (NCDB) was queried for metastatic GEP-NECs from 2009 to 2016. The cohort was stratified by patients who had received chemotherapy and who did not receive chemotherapy. Demographic, socioeconomic, clinical, and treatment characteristics were captured. Multivariable logistic regression examined factors associated with chemotherapy utilization.

RESULTS

Of the 2367 stage IV GEP-NECs patients identified, 1647 (69.6%) received chemotherapy. Patients with primary site at colon and small bowel, age ≥75, no insurance, and ≥2 comorbidities were less likely to receive chemotherapy than patients with other primary sites, age <75, private insurance, and no comorbidities (P < 0.005). The small bowel and colon were the primary sites with the greatest percentage of patients who received surgery (46.4% and 41.8%, respectively). In these subgroup of patients, surgical intervention was also associated with lower probability of receiving chemotherapy (odds ratio = 0.60, P < 0.005).

CONCLUSIONS

About 30% of patients with metastatic GEP-NECs did not receive chemotherapy. Primary site location and receipt of surgery were significantly associated with receipt of chemotherapy, with NECs in small bowel and colon being more likely to receive surgery and less likely to receive chemotherapy. While surgery may be considered on an individual basis, increasing efforts to ensure patients with colon or small bowel NECs receive guideline-concordant chemotherapy will positively impact survival. In addition, interventions to improve health insurance coverage to increase receipt of chemotherapy are warranted.

Aberrant circulating tumor DNA methylation and exosomal microRNA biomarkers for early detection of colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) became the third most commonly diagnosed malignancy and the second leading cause of cancer death in 2020. However, the rates of early screening and early diagnosis for CRC remain unsatisfactory. Thus, it is essential to explore the initiating factors of CRC and strategies for its early diagnosis. Research progress in liquid biopsy has led to the finding that circulating tumor-derived DNA (ctDNA) and exosomes play vital roles in early detection of CRC. THE APPLICATIONS OF LIQUID BIOPSY FOR EARLY DETECTION OF COLORECTAL CANCER: Moreover, the increased understanding of epigenetics has highlighted the role of ctDNA methylation in CRC carcinogenesis, and the detection of aberrant ctDNA methylation markers is a feasible strategy for diagnosis of early-stage CRC. Among exosomal markers, microRNAs (miRNAs) are abundant and are the most researched. Upregulated or downregulated expression of exosome-derived miRNAs can indicate the occurrence of early-stage CRC.

FUTURE PERSPECTIVE

The current research progress on aberrant ctDNA methylation and tumor exosomal miRNA biomarkers in early detection of CRC is summarized in this review, and the advantages and shortcomings of the methods are discussed.

Transcriptomic data analysis coupled with copy number aberrations reveals a blood-based 17-gene signature for diagnosis and prognosis of patients with colorectal cancer

Background: Colorectal cancer (CRC) is the third most common cancer and third leading cause of cancer-associated deaths worldwide. Diagnosing CRC patients reliably at an early and curable stage is of utmost importance to reduce the risk of mortality. Methods: We identified global differentially expressed genes with copy number alterations in patients with CRC. We then identified genes that are also expressed in blood, which resulted in a blood-based gene signature. We validated the gene signature's diagnostic and prognostic potential using independent datasets of gene expression profiling from over 800 CRC patients with detailed clinical data. Functional enrichment, gene interaction networks and pathway analyses were also performed. Results: The analysis revealed a 17-gene signature that is expressed in blood and demonstrated that it has diagnostic potential. The 17-gene SVM classifier displayed 99 percent accuracy in predicting the patients with CRC. Moreover, we developed a prognostic model and defined a risk-score using 17-gene and validated that high risk score is strongly associated with poor disease outcome. The 17-gene signature predicted disease outcome independent of other clinical factors in the multivariate analysis (HR = 2.7, 95% CI = 1.3-5.3, p = 0.005). In addition, our gene network and pathway analyses revealed alterations in oxidative stress, STAT3, ERK/MAPK, interleukin and cytokine signaling pathways as well as potentially important hub genes, including BCL2, MS4A1, SLC7A11, AURKA, IL6R, TP53, NUPR1, DICER1, DUSP5, SMAD3, and CCND1. Conclusion: Our results revealed alterations in various genes and cancer-related pathways that may be essential for CRC transformation. Moreover, our study highlights diagnostic and prognostic value of our gene signature as well as its potential use as a blood biomarker as a non-invasive diagnostic method. Integrated analysis transcriptomic data coupled with copy number aberrations may provide a reliable method to identify key biological programs associated with CRC and lead to improved diagnosis and therapeutic options.

Primary tumor resection in colorectal cancer patients with unresectable distant metastases: a minireview

Colorectal cancer (CRC) is the second most common cause of cancer-related death among both men and women worldwide and the third most common cancer overall. About 20% of patients diagnosed with CRC were discovered to have distant metastatic lesions, the majority of which were located in the liver. For the optimum treatment of CRC patients with hepatic metastases, interventional radiologists, medical oncologists, and surgeons must all collaborate. The surgical excision of the primary tumor is an important part of CRC treatment since it has been found to be curative in cases of CRC with minimal metastases. However, given the evidence to date was gathered from retrospective data, there is still controversy over the effectiveness of primary tumor resection (PTR) in improving the median overall survival (OS) and quality of life. Patients who have hepatic metastases make up a very tiny fraction of those who are candidates for resection. With a focus on the PTR, this minireview attempted to review the current advancements in the treatment options for hepatic colorectal metastatic illness. This evaluation also included information on PTR's risks when performed on individuals with stage IV CRC.

Treatment of Metastatic Colorectal Cancers in Resource-Constrained Low- and Middle-Income Countries (LMICS) Scenario-Outcomes, Practice Patterns, and Commentary on Treatment Costs

Anant RamaswamyIntroduction  The overall survival (OS) of metastatic colorectal cancers (mCRCs) in clinical practice and resource-constrained low- and middle-income countries (LMICS) like India is not known. Materials and Methods  Data of patients with mCRC treated between January 2013 and August 2017 were accessed from a prospectively maintained database. Demographics, disease characteristics, chemotherapeutic regimens, use of monoclonal antibodies, and survival outcomes in treated patients were collected and analyzed. Costs of treatment options as off 2017 were also interpreted. Results  The data of 403 patients satisfied prespecified inclusion criteria and were included for analysis. The median age of the cohort was 48 years (range: 17-86) with a predominance of rectal cancers (63.3%), liver alone metastases (47.1%), and resected primary (69.7%). Signet ring histology was present in 82 patients (20.3%). The most commonly used first-line regimen (CT1) was modified capecitabine-oxaliplatin (53.3%). Two hundred and nineteen patients (54.3%) received second-line systemic therapy (CT2). Patients received a median of two lines of therapy (range: 1-6). MoAbs were used by 48 patients (13.4%) with CT1 and 34 patients (15.5%) with CT2. Median OS of the entire cohort was 17.61 months (95% confidence interval: 15.48-19.74), which was within the predicted range, as per investigator hypothesis. The presence of signet ring histology ( p <0.001), raised carcinoembryonic antigen at baseline ( p =0.017), and the absence of a resected primary ( p <0.001) predicted inferior median OS. Conclusions  Survival of patients with mCRC in a resource-constrained LMIC scenario like India is approximately 12 to 15 months lower than published trial data. Limited access to targeted therapy and newer expensive treatment options due to financial constraints may contribute to this disparity.

An internalizing antibody targeting of cell surface GRP94 effectively suppresses tumor angiogenesis of colorectal cancer

Colorectal cancer (CRC) is one of the life-threatening malignancies worldwide. Thus, novel potential therapeutic targets and therapeutics for the treatment of CRC need to be identified to improve the clinical outcomes of patients with CRC. In this study, we found that glucose-regulated protein 94 (GRP94) is overexpressed in CRC tissues, and its high expression is correlated with increased microvessel density. Next, through phage display technology and consecutive in vitro functional isolations, we generated a novel human monoclonal antibody that specifically targets cell surface GRP94 and shows superior internalizing activity comparable to trastuzumab. We found that this antibody specifically inhibits endothelial cell tube formation and simultaneously promotes the downregulation of GRP94 expression on the endothelial cell surface. Finally, we demonstrated that this antibody effectively suppresses tumor growth and angiogenesis of HCT116 human CRC cells without causing severe toxicity in vivo. Collectively, these findings suggest that cell surface GRP94 is a novel potential anti-angiogenic target in CRC and that antibody targeting of GRP94 on the endothelial cell surface is an effective strategy to suppress CRC tumor angiogenesis.

Inoperable de novo metastatic colorectal cancer with primary tumour in situ: Evaluating discordant responses to upfront systemic therapy of the primary tumours and metastatic sites and complications arising from primary tumours (experiences from an Irish Cancer Centre)

Systemic therapy is the mainstay of treatment for de novo metastatic colorectal cancer (mCRC). Heterogeneity between primary tumours and metastases may lead to discordant responses to systemic therapy at these sites. The aim of the present study was to examine these discrepancies and to evaluate the rates of complications arising from the primary tumour and the strategies employed to manage these complications. Electronic medical records were screened for patients eligible for data analysis between January 1st, 2014 and December 31st, 2019. All patients diagnosed with de novo mCRC with primary tumour in situ at the time of initial systemic therapy were included in data analysis. Responses in primary tumour and metastatic sites (according to the Response Evaluation Criteria In Solid Tumours v1.1), discrepancies in these responses and rates of complications arising from primary tumours were assessed along with patient, pathological or molecular factors that may be associated with these discrepant responses or primary tumour complications. A total of 50 patients were identified (median age, 62 years). Right-colon, left-colon and rectal primary tumours comprised 34, 44 and 22% of CRC cases, respectively. All patients received 5-fluorouracil-based chemotherapy (either alone or in combination with oxaliplatin or irinotecan). Disease response (DR), stable disease (SD) and progressive disease (PD) were observed as the first response to systemic therapy in 24, 62 and 12% of primary tumours and in 36, 18 and 44% of metastatic sites, respectively. Only 36% of patients demonstrated concordant responses between the primary tumours and metastases, while the remaining 62% demonstrated discordant responses between the primary tumour and distant metastases (22% had DR with SD; 36% had DR or SD with PD; and 4% had PD with SD in the primary tumour and metastases, respectively). Restaging images were not available for 2% of the patients. Approximately 30% of patients developed complications from primary tumours, including bowel obstruction (6.12%), perforation (6%), rectal pain (6%) and rectal bleeding (10%). Approximately 10% of patients underwent palliative stoma creation. Additionally, 12% required palliative radiotherapy to the primary tumour (due to localized complications arising from the tumour). Discordant responses to systemic therapy between primary tumours and metastases occurred in 60% of patients with de novo mCRC (with primary tumour in situ at the time of first systemic therapy). The observations of the present study have potential implications for molecular tissue analysis to help guide systemic therapy. Tissue from metastatic sites may be preferable to confirm biomarker status in mCRC based on this study.

Colorectal Cancer, Liver Metastases and Biotherapies

(1) Background: colorectal cancer (CRC) is one of the deadliest causes of death by cancer worldwide. Its first main metastatic diffusion spreads to the liver. Different mechanisms such as the epithelial-mesenchymal transition and angiogenesis are the characteristics of this invasion. At this stage, different options are possible and still in debate, especially regarding the use of targeted therapeutics and biotherapies. (2) Methods: A review of the literature has been done focusing on the clinical management of liver metastasis of colorectal cancer and the contribution of biotherapies in this field. (3) Results: In a clinical setting, surgeons and oncologists consider liver metastasis in CRC into two groups to launch adapted therapeutics: resectable and non-resectable. Around these two entities, the combination of targeted therapies and biotherapies are of high interest and are currently tested to know in which molecular and clinical conditions they have to be applied to impact positively both on survival and quality of life of patients.

Analyzing the Opportunities to Target DNA Double-Strand Breaks Repair and Replicative Stress Responses to Improve Therapeutic Index of Colorectal Cancer

Despite the ample improvements of CRC molecular landscape, the therapeutic options still rely on conventional chemotherapy-based regimens for early disease, and few targeted agents are recommended for clinical use in the metastatic setting. Moreover, the impact of cytotoxic, targeted agents, and immunotherapy combinations in the metastatic scenario is not fully satisfactory, especially the outcomes for patients who develop resistance to these treatments need to be improved. Here, we examine the opportunity to consider therapeutic agents targeting DNA repair and DNA replication stress response as strategies to exploit genetic or functional defects in the DNA damage response (DDR) pathways through synthetic lethal mechanisms, still not explored in CRC. These include the multiple actors involved in the repair of DNA double-strand breaks (DSBs) through homologous recombination (HR), classical non-homologous end joining (NHEJ), and microhomology-mediated end-joining (MMEJ), inhibitors of the base excision repair (BER) protein poly (ADP-ribose) polymerase (PARP), as well as inhibitors of the DNA damage kinases ataxia-telangiectasia and Rad3 related (ATR), CHK1, WEE1, and ataxia-telangiectasia mutated (ATM). We also review the biomarkers that guide the use of these agents, and current clinical trials with targeted DDR therapies.

Impact of anatomic site of distant metastasis on survival in salivary gland cancers

BACKGROUND

As exemplified in patients with adenoid cystic carcinoma (ACC), metastatic salivary gland cancers display heterogenous behavior. Although anatomic site of metastasis has been suggested to be prognostic for survival in this population, this is not adequately characterized in the current literature.

METHODS

Using the National Cancer Database (NCDB), patients with newly diagnosed metastatic salivary gland cancers with distant metastasis to a single organ were identified.

RESULTS

Eight hundred and fifty-eight patients (n = 284 bone-only, n = 322 lung-only, n = 252 other-site-only) were identified. Anatomic site of distant metastasis was not associated with survival in the cohort as a whole; however, on pre-planned subgroup analysis, lung-only metastasis, relative to bone-only metastasis, was the only factor associated with improved survival in patients with ACC (HR: 0.52, 95%CI: 0.30-0.93, p = 0.029).

CONCLUSIONS

Anatomic site of metastasis is strongly associated with survival in patients with metastatic ACC and should be considered in future studies aiming to optimize therapy in this population.

The Impact of Primary Tumor Resection on Survival in Asymptomatic Colorectal Cancer Patients With Unresectable Metastases

Purpose

This study was conducted to evaluate the effectiveness of primary tumor resection (PTR) in asymptomatic colorectal cancer (CRC) patients with unresectable metastases using the inverse probability of treatment weighting (IPTW) method to minimize selection bias.

Methods

We selected 146 patients diagnosed with stage IV CRC with unresectable metastasis between 2001 and 2018 from our institutional database. In a multivariate logistic regression model using the patients’ baseline covariates associated with PTR, we applied the IPTW method based on a propensity score and performed a weighted Cox proportional regression analysis to estimate survival according to PTR.

Results

Upfront PTR was performed in 98 patients, and no significant differences in baseline factors were detected. The upweighted median survival of the PTR group was 18 months and that of the non-PTR group was 15 months (P = 0.15). After applying the IPTW, the PTR was still insignificant in the univariate Cox regression (hazard ratio [HR], 0.26; 95% confidence interval [CI], 0.5–1.21). However, in the multivariate weighted Cox regression with adjustment for other covariates, the PTR showed a significantly decreased risk of cancer-related death (HR, 0.61; 95% CI, 0.40–0.94).

Conclusion

In this study, we showed that asymptomatic CRC patients with unresectable metastases could gain a survival benefit from upfront PTR by analysis with the IPTW method. However, randomized controlled trials are mandatory.

Proteomics study of colorectal cancer and adenomatous polyps identifies TFR1, SAHH, and HV307 as potential biomarkers for screening

Colorectal cancer (CRC) is a malignant tumour with high morbidity and mortality worldwide. Efficient screening strategies for CRC and pre-cancerous lesions can promote early medical intervention and treatment, thereby reducing morbidity and mortality. Proteins are generally considered key biomarkers of cancer. Herein, we performed a quantitative, original-tissue proteomics study in a cohort of ninety patients from pre-cancerous to cancerous conditions via liquid chromatography-tandem mass spectrometry. In total, 134,812 peptides, 8697 proteins, 2355 union differentially expressed proteins (DEPs), and 409 shared DEPs (compared with adjacent tissues) were identified. The number of DEPs indicated a positive correlation with increasing severity of illness. The union and shared DEPs were both enriched in the KEGG pathway of focal adhesion, metabolism of xenobiotics by cytochrome P450, and drug metabolism by cytochrome P450. Among the 2355 union DEPs, 32 were selected for identification and validation by multiple reaction monitoring from twenty plasma specimens. Of these, three proteins, transferrin receptor protein 1 (TFR1), adenosylhomocysteinase (SAHH), and immunoglobulin heavy variable 3-7 (HV307), were significantly differentially expressed and displayed the same expression pattern in plasma as observed in the tissue data. In conclusion, TFR1, SAHH, and HV307 may be considered as potential biomarkers for CRC screening. SIGNIFICANCE: Although CRC is a malignant tumour with high morbidity and mortality worldwide, efficient screening strategies for CRC and pre-cancerous lesions can play an important role in addressing these issues. Screening of molecular biomarkers provide a non-invasive, cost-effective, and efficient approach. Proteins are generally considered key molecular biomarkers of cancer. Our study reports a quantitative proteomics analysis of protein biomarkers for colorectal cancer (CRC) and adenomatous polyps, and identifies TFR1, SAHH, and HV307 as potential biomarkers for screening. This research makes a significant contribution to the literature as although mass spectrometry-based proteomics research has been widely used for clinical research, its application to clinical translation as parallel specimens ranging from pre-cancerous to cancerous tissues-according to the degree of disease progression-has not been readily assessed.

Multimodal Treatment in Metastatic Colorectal Cancer (mCRC) Improves Outcomes-The University College London Hospital (UCLH) Experience

BACKGROUND

Despite notable advances in the management of metastatic colorectal cancer (mCRC) over the last two decades, treatment intent in the vast majority of patients remains palliative due to technically unresectable disease, extensive disease, or co-morbidities precluding major surgery. Up to 30% of individuals with mCRC are considered potentially suitable for primary or metastasis-directed multimodal therapy, including surgical resection, ablative techniques, or stereotactic radiotherapy (RT), with the aim of improving survival outcomes. We reviewed the potential benefits of multimodal therapy on the survival of patients with mCRC treated at the UCLH.

METHODS

Clinical data on baseline characteristics, multimodal treatments, and survival outcomes were retrospectively collected from all patients with mCRC receiving systemic chemotherapy between January 2013 and April 2017. Primary outcome was the impact of multimodal therapy on overall survival, compared to systemic therapy alone, and the effect of different types of multimodal therapy on survival outcome, and was assessed using the Kaplan-Meier approach. All analyses were adjusted for age, gender, and side of primary tumour.

RESULTS

One-hundred and twenty-five patients with mCRC were treated during the study period (median age: 62 years (range 19-89). The liver was the most frequent metastatic site (78%; 97/125). A total of 52% (65/125) had ≥2 lines of systemic chemotherapy. Of the 125 patients having systemic chemotherapy, 74 (59%) underwent multimodal treatment to the primary tumour or metastasis. Median overall survival (OS) was 25.7 months [95% Confidence Interval (CI) 21.5-29.0], and 3-year survival, 26%. Univariate analysis demonstrated that patients who had additional procedures (surgery/ablation/RT) were significantly less likely to die (Hazard Ratio (HR) 0.18, 95% CI 0.12-0.29, p < 0.0001) compared to those receiving systemic chemotherapy alone. Increasing number of multimodal procedures was associated with an incremental increase in survival-with median OS 28.4 m, 35.7 m, and 64.8 m, respectively, for 1, 2, or ≥3 procedures (log-rank p < 0.0001). After exclusion of those who received systemic chemotherapy only (n = 51), metastatic resections were associated with improved survival (adjusted HR 0.36, 95% CI 0.20-0.63, p < 0.0001), confirmed in multivariate analysis. Multiple single-organ procedures did not improve survival.

CONCLUSION

Multimodal therapy for metastatic bowel cancer is associated with significant survival benefit. Resection/radical RT of the primary and resection of metastatic disease should be considered to improve survival outcomes following multidisciplinary team (MDT) discussion and individual assessment of fitness.

Molecular Immunotherapy: Promising Approach to Treat Metastatic Colorectal Cancer by Targeting Resistant Cancer Cells or Cancer Stem Cells

The immune system is able to recognize and eliminate tumor cells. Some tumors, including colorectal cancer (CRC), induce immune tolerance via different mechanisms of “immunoediting” and “immune evasion” and can thus escape immune surveillance. The impact of immunotherapy on cancer has been investigated for many years, but so far, the application was limited to few cancer types. Immuno-oncological therapeutic strategies against metastatic colorectal cancer (mCRC), the adaptive immune system activating approaches, offer a high potential for adaptation to the great heterogeneity of CRC. Moreover, novel treatment approaches are currently being tested that might specifically target the disease initiating and maintaining population of colorectal cancer stem cells (CSCs). In this review, we aim to summarize the current state of immune-oncology and tumor immunotherapy of patients with mCRC and discuss different therapeutic modalities that focus on the activation of tumor-specific T-cells and their perspectives such as tumor vaccination, checkpoint inhibition, and adoptive T-cell transfer or on the eradication of colorectal CSCs.

Surgery improves the prognosis of colon mucinous adenocarcinoma with liver metastases: a SEER-based study

BACKGROUND

Mucinous adenocarcinoma (MC) is the second most common pathological type of colon carcinoma (CC). Colon cancer liver metastases (CLMs) are common and lethal, and complete resection of the primary tumour and metastases for CLM patients would be beneficial. However, there is still no consensus on the role of surgery for MC with liver metastases (M-CLM).

METHODS

Patients diagnosed with M-CLM or classical adenocarcinoma with CLM (A-CLM) from 2010 to 2013 in the Surveillance, Epidemiology, and End Results (SEER) database were retrieved. The clinicopathological features and overall survival (OS) and cancer-specific survival (CSS) data were compared and analysed.

RESULTS

The results showed that the M-CLM group had a larger tumour size, more right colon localizations, higher pT and pN stages, more female patients, and more retrieved and positive lymph nodes and accounted for a higher proportion of surgeries than the A-CLM group. The OS and CSS of M-CLM patients who underwent any type of surgery were significantly better than those of patients who did not undergo any surgery, but poorer than those of A-CLM patients who underwent surgery. Meanwhile, the OS and CSS of M-CLM and A-CLM patients who did not undergo any surgery were comparable. Compared with hemicolectomy, partial colectomy led to similar or better OS and CSS for M-CLM, and surgery was an independent protective factor for long-term survival in M-CLM.

CONCLUSIONS

M-CLM had distinct clinicopathological characteristics from A-CLM, and surgery could improve the survival and is an independent favourable prognostic factor for M-CLM. In addition, partial colectomy might be a non-inferiority choice as hemicolectomy for M-CLM according to the results from this study.

Colonic stent vs surgical resection of the primary tumor. Effect on survival from stage-IV obstructive colorectal cancer

BACKGROUND AND OBJECTIVES

the impact of surgical primary tumor resection on survival of obstructive metastatic colorectal cancer remains controversial. The primary goal of this study was to analyze survival in patients with obstructive metastatic colorectal cancer after treatment with either resection surgery or a colonic stent.

MATERIAL AND METHODS

a prospective study was performed of all patients with stage-IV colorectal cancer and obstructive manifestations, diagnosed from 2005 to 2012 and managed with either resection surgery or a colonic stent. Cases with a perforation, abscess, right colon or distal rectal malignancy, multiple colorectal cancer or derivative surgery were excluded.

RESULTS

a total of 95 patients were included, 49 were managed with resection surgery and 46 with a colonic stent. The colonic stent group had a higher Charlson index (9.5 ± 2.1 vs 8.6 ± 1.5, p = 0.01), a shorter time to oral intake (0.9 ± 1.1 vs 16.4 ± 53.5 days, p = 0.05), a shorter hospital stay (4 ± 4.8 vs 16.7 ± 15.5 days, p = 0.0001), less need for stomata (11.1 % vs 32.7 %, p = 0.01), fewer early complications (4.3 % vs 46.9 %, p = 0.0001) and more late complications (33.3 % vs 6.4 %, p = 0.001). Undergoing chemotherapy (p = 0.008) was the only independent factor related to increased survival. In the subgroup of patients managed with chemotherapy, surgical primary tumor resection was an independent factor associated with increased survival.

CONCLUSION

both treatments are effective for resolving obstructive manifestations in patients diagnosed with stage-IV obstructive colorectal cancer. Resection surgery has no positive impact on survival and thus cannot be recommended as a therapy of choice.

Evaluation of Second-line Anti-VEGF after First-line Anti-EGFR Based Therapy in RAS Wild-Type Metastatic Colorectal Cancer: The Multicenter "SLAVE" Study

: Background: The optimal anti-angiogenic strategy as second-line treatment in RAS wild-type metastatic colorectal cancer (mCRC) treated with anti-EGFR (Epidermal Growth Factor Receptor) based first-line treatment is still debated.

METHODS

This multicenter, real-world, retrospective study is aimed at evaluating the effectiveness of second-line Bevacizumab- and Aflibercept-based treatments after an anti-EGFR based first-line regimen. Clinical outcomes measured were: objective response rate (ORR), progression free survival (PFS), overall survival (OS) and adverse events (AEs) profiles.

RESULTS

From February 2011 to October 2019, 277 consecutive mCRC patients received Bevacizumab-based (228, 82.3%) or Aflibercept-based (49, 17.7%) regimen. No significant difference was found regarding ORR. The median follow-up was 27.7 months (95%CI: 24.7-34.4). Aflibercept-treated group had a significantly shorter PFS compared to Bevacizumab-treated group (5.6 vs. 7.1 months, respectively) (HR = 1.34 (95%CI: 0.95-1.89); p = 0.0932). The median OS of the Bevacizumab-treated group and Aflibercept-treated group was 16.2 (95%CI: 15.3-18.1) and 12.7 (95%CI: 8.8-17.5) months, respectively (HR= 1.31 (95%CI: 0.89-1.93) p = 0.16). After adjusting for the key covariates (age, gender, performance status, number of metastatic sites and primary tumor side) Bevacizumab-based regimens revealed to be significantly related with a prolonged PFS (HR = 1.44 (95%CI: 1.02-2.03); p = 0.0399) compared to Aflibercept-based regimens, but not with a prolonged OS (HR = 1.47 (95%CI: 0.99-2.17); p = 0.0503). The incidence of G3/G4 VEGF inhibitors class-specific AEs was 7.5% and 26.5% in the Bevacizumab-treated group and the Aflibercept-treated group, respectively (p = 0.0001).

CONCLUSION

Our analysis seems to reveal that Bevacizumab-based regimens have a slightly better PFS and class-specific AEs profile compared to Aflibercept-based regimen as second-line treatment of RAS wild-type mCRC patients previously treated with anti-EGFR based treatments. These results have to be taken with caution and no conclusive considerations are allowed.

The challenges in colorectal cancer management during COVID-19 epidemic

It has been over 2 months since the start of the Coronavirus disease 2019 (COVID-19) outbreak. The epidemic stage of COVID-19 has brought great challenges to the diagnosis and management of colorectal cancer (CRC) patients. Symptoms, such as fever and cough caused by cancer, and the therapeutic process (including chemotherapy and surgery) should be differentiated from some COVID-19 related characteristics. Besides, clinical workers should not only consider the therapeutic strategy for cancer, but also emphasize COVID-19's prevention. Moreover, the detailed therapeutic regimens of CRC patients may be different from the usual. Also, treatment principles may various for CRC patients with or without severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, as well as patients with or without an emergency presentation. In this paper, we want to discuss the above-mentioned problems based on previous guidelines, the current working status and our experiences, to provide a reference for medical personnel.

Does primary tumor resection contribute to overall survival in unresectable synchronous metastatic colorectal cancer?

BACKGROUND

Primary tumor resection (PTR) in metastatic colorectal cancer (mCRC) has not been suggested by guidelines, since new systemic chemotherapy options have improved overall survival. However, the effect of PTR is still controversial in mCRC. In this study, we aimed to evaluate the effect of PTR on survival in unresectable mCRC.

MATERIALS AND METHODS

Two hundred and fifty-two patients with unresectable mCRC were screened retrospectively between January 2007 and December 2017 and a total of 147 patients who met inclusion criteria were included. The patients with emergency or elective PTR and the patients without surgery were compared for baseline features and overall survival.

RESULTS

The median follow-up time was 15.6 months (range; 1.2-78.9) in whole patients. There were 91 patients in nonsurgical (NS) group and 56 patients in PTR group. The median overall survival was significantly longer in PTR group compared NS group (21.8 vs. 17.0 months, P = 0.01), but it was not associated to better overall survival in multivariate Cox analysis (hazard ratio: 0.65, 95% confidence interval: 0.41-1.02, P = 0.06). There was no significant difference in overall survival between emergency and elective surgery subgroups (22.9 vs. 16.1 months, respectively, P = 0.9).

CONCLUSION

PTR did not offer an overall survival benefit in this study. Although it is debated, we think that it is better to start treatment with chemotherapy and biological agent combinations in patients with asymptomatic mCRC. Thus, the patients can be protected from the morbidity and mortality of the surgery.

National statistics about resection of the primary tumor in asymptomatic patients with Stage IV colorectal cancer and unresectable metastases. Need for improvement in data collection. A systematic review with meta-analysis

BACKGROUND

Patients with asymptomatic Stage IV colorectal cancer represent a significant heterogeneous group. National statistics represent an effective method to follow in real time the clinical outcomes of patients, and they may represent an important tool to analyze and to compare different therapeutic approaches. The aim of our study was to analyze the reviews of national data and single institutions reports, which compared the clinical outcomes of patients with asymptomatic Stage IV colorectal cancer and un-resectable metastases who had resection of the primary tumor with those who did not have resection. We gave special attention to the number of missing established relevant variables, to determine the appropriateness of the results of the published studies.

MATERIAL

We performed a systematic review of papers comparing patients who had and who had not primary tumor resection. Screened reports included the time of publication from June 2012 to June 2018; 2556 papers were identified and 27 were included into the review. The primary outcome was observed survival. We analyzed the number of major missing variables in National Data Bases and Single Institution Reports, to assess the overall validity of the conclusions of the analyzed reports.

RESULTS

In the majority of the reports and in the meta-analysis of studies with propensity score matching, resection of the primary tumor was correlated to improved survival and to the possibility for a better response to postoperative chemotherapy.

CONCLUSIONS

The high number of missing significant variables, and a clear clinical selection in single center reports make any analysis error-prone. National statistics might represent a valid method to follow in real time the clinical outcomes of these patients, comparing different therapeutic approaches. There is the need for improvement in national data collection, to make descriptive national statistics the ground for future progress in treatment. (PROSPERO) CRD 42018089691.

Endoscopic stenting in colorectal cancer

Acute malignant large bowel obstruction presents as one of the few emergencies of colorectal cancer (CRC). Management of this condition can either be by (I) upfront surgery or (II) the use of self-expanding metallic stent (SEMS) as a bridge to elective surgery. For patients with metastasis, the use of SEMS is reported to enable earlier commencement of chemotherapy. Although the use of SEMS in patients with acute malignant large bowel obstruction looks promising, it is plagued by its own set of complications and divided opinion over its long-term outcomes. Conflicting data are present, and definitive indication requires further evaluation and debate. This article will describe the typical presentation of patients with acute malignant large bowel obstruction. An introduction to the SEMS insertion procedural steps will be undertaken. Following which the article aims to review the safety profile of SEMS and the short- and long-term outcomes of SEMS in both the curative and palliative setting.

Biomarkers in Colorectal Cancer: The Role of Translational Proteomics Research

Colorectal cancer is one of the most common cancers in the world, and it is one of the leading causes of cancer-related death. Despite recent progress in the development of screening programs and in the management of patients with colorectal cancer, there are still many gaps to fill, ranging from the prevention and early diagnosis to the determination of prognosis factors and treatment of metastatic disease, to establish a personalized approach. The genetic profile approach has been increasingly used in the decision-making process, especially in the choice of targeted therapies and in the prediction of drug response, but there are still few validated biomarkers of colorectal cancer for clinical practice. The discovery of non-invasive, sensitive, and specific biomarkers is an urgent need, and translational proteomics play a key role in this process, as they enable better comprehension of colorectal carcinogenesis, identification of potential markers, and subsequent validation. This review provides an overview of recent advances in the search for colorectal cancer biomarkers through proteomics studies according to biomarker function and clinical application.

Prognostic value of chloride channel accessory mRNA expression in colon cancer

Chloride channel accessory (CLCA) is a gene family that encode Ca²⁺ activated chloride channels, which make a substantial contribution to various diseases. The aim of the present study was to investigate the prognostic value of CLCA expression in colon cancer. In an attempt to elucidate the value of CLCA mRNA expression in the prognosis of patients with colon cancer, the gene expression data of 438 patients with colon cancer were analyzed. The source of the data was The Cancer Genome Atlas, and it was identified that high expression levels of CLCA1 and CLCA2 were associated with a favorable overall survival (OS) time in patients with colon cancer. As revealed by joint effects analysis, the co-occurrence of high expression levels of CLCA1 and CLCA2 was associated with a favorable OS time in patients with colon cancer. CLCA genes were investigated using gene set enrichment analysis. The results of the bioinformatics analysis demonstrated that high expression levels of CLCA1 and CLCA2 were associated with the prognosis of colon cancer. These findings suggest that CLCA1 and CLCA2 are potential prognostic biomarkers for patients with colon cancer. Furthermore, combining CLCA1 and CLCA2 can enhance the sensitivity of the prediction of the OS time of patients with colon cancer.

Colorectal liver metastases: An update on multidisciplinary approach

Liver metastasis is the commonest form of distant metastasis in colorectal cancer. Selection criteria for surgery and liver-directed therapies have recently been extended. However, resectability remains poorly defined. Tumour biology is increasingly recognized as an important prognostic factor; hence molecular profiling has a growing role in risk stratification and management planning. Surgical resection is the only treatment modality for curative intent. The most appropriate surgical approach is yet to be established. The primary cancer and the hepatic metastasis can be removed simultaneously or in a two-step approach; these two strategies have comparable long-term outcomes. For patients with a limited future liver remnant, portal vein embolization, combined ablation and resection, and associating liver partition and portal vein ligation for staged hepatectomy have been advocated, and each has their pros and cons. The role of neoadjuvant and adjuvant chemotherapy is still debated. Targeted biological agents and loco-regional therapies (thermal ablation, intra-arterial chemo- or radio-embolization, and stereotactic radiotherapy) further improve the already favourable results. The recent debate about offering liver transplantation to highly selected patients needs validation from large clinical trials. Evidence-based protocols are missing, and therefore optimal management of hepatic metastasis should be personalized and determined by a multi-disciplinary team.

Outcome of chemotherapy with or without targeted agents in metastatic colorectal cancer patients with deficient DNA mismatch repair: A single center, cohort study

AIMS

Metastatic colorectal cancer (mCRC) with deficient DNA mismatch repair (dMMR) is a rare disease accounting only for 4-5% of the whole mCRC and its optimal treatment still remains unclear. We conducted a retrospective study to evaluate the outcome of chemotherapy with or without bevacizumab or cetuximab in this setting.

METHODS

A total of 729 colorectal cancer patients with dMMR status were screened for eligibility. The Kaplan-Meier method, the log-rank test and Cox analysis were utilized for survival analyses.

RESULTS

A total of 43 patients met the inclusion criteria and enrolled in the study. The median overall survival (OS) of entire cohort was 21.7 months. Chemotherapy plus bevacizumab group exhibited a tendency of substantially higher overall response rate (ORR) than chemotherapy alone group (63.6% vs. 23.8%, P = 0.053), whereas the ORR between chemotherapy plus cetuximab group and chemotherapy alone group were similar (28.6% vs. 23.8%, P = 1.000). Compared with chemotherapy alone group, bevacizumab combined group achieved a significantly longer progression-free survival (10.0 months vs. 4.8 months, P = 0.028), whereas cetuximab combined group was not (6.8 months vs. 4.8 months, P = 0.158). Although the median OS seemed to favor bevacizumab combined group, no significant differences were detected between the three arms (33.7, 21.7 and 15.3 months, respectively; P = 0.345). Prognostic analysis showed that primary tumor resection was the positive prognostic factor of OS (hazards ratio: 0.438; P = 0.041).

CONCLUSION

dMMR mCRC seems resistant to chemotherapy and cetuximab. Bevacizumab combined therapy shows a sign of potentially favorable outcome in this subtype.

Primary tumor resection in stage IV unresectable colorectal cancer: what has changed?

Most current guidelines do not recommend primary tumor resection in stage IV unresectable colorectal cancer. Rapid chemotherapy development over the last decade has substantially changed the decision making. However, results of recently published trials and meta-analyses suggest that primary tumor resection may in fact be beneficial, principally in terms of prolonged survival. Additional factors, such as use of minimally invasive approach or protocols of enhanced recovery after surgery, affect clinical outcomes as well, but are often neglected when discussing the state of the art in this area. There are still no randomized studies determining the legitimacy of upfront surgery in asymptomatic patients. Also, quality of life also plays an important role in choosing appropriate treatment. Having said that, there is no data that would prove whether primary tumor resection has an advantage on that issue. With all the uncertainty, currently decision making in unresectable stage IV colorectal cancer is primarily up to clinicians' knowledge, common sense and patients' preferences.

Primary tumor location as a predictor of the benefit of palliative resection for colorectal cancer with unresectable metastasis

Background

It is still under debate that whether stage IV colorectal cancer patients with unresectable metastasis can benefit from primary tumor resection, especially for asymptomatic colorectal cancer patients. Retrospective studies have shown controversial results concerning the benefit from surgery. This retrospective study aims to evaluate whether the site of primary tumor is a predictor of palliative resection in asymptomatic stage IV colorectal cancer patients.

Methods

One hundred ninety-four patients with unresectable metastatic colorectal cancer were selected from Sun Yat-sen University Cancer Center Database in the period between January 2007 and December 2013. All information was carefully reviewed and collected, including the treatment, age, sex, carcinoembryonic antigen, site of tumor, histology, cancer antigen 199, number of liver metastases, and largest diameter of liver metastasis. The univariate and multivariate analyses were used to detect the relationship between primary tumor resection and overall survival of unresectable stage IV colorectal cancer patients.

Results

One hundred twenty-five received palliative resection, and 69 received only chemotherapy. Multivariate analysis indicated that primary tumor site was one of the independent factors (RR 0.569, P = 0.007) that influenced overall survival. For left-side colon cancer patients, primary tumor resection prolonged the median overall survival time for 8 months (palliative resection vs. no palliative resection: 22 vs. 14 months, P = 0.009); however, for right-side colon cancer patients, palliative resection showed no benefit (12 vs. 10 months, P = 0.910).

Conclusions

This study showed that left-side colon cancer patients might benefit from the primary tumor resection in terms of overall survival. This result should be further explored in a prospective study.